CCNA FAQ: VLSMs, Summarization, and Troubleshooting TCP/IP Q1. On a VLSM network, which mask should you use on point-to-point WAN links in order to reduce the waste of IP addresses? A. /27 B. /28 C. /29 D. /30 E. /31 Answer: D. A point-to-point link uses only two hosts. A /30, or 255.255.255.252, mask provides […]